1. Field of the Invention
The present invention relates to a stereoscopic X-ray apparatus which permits stereoscopic observation of a subject under examination using a number of X-ray images of the subject obtained by emitting X-rays from an X-ray tube to the subject from many directions and at regular intervals while rotating the X-ray tube around the subject.
2. Description of the Related Art
According to a conventional stereoscopic X-ray apparatus, an X-ray tube and an image intensifier are supported by a C-shaped arm, and the arm is rotated so that the X-ray tube and the image intensifier rotate around a subject under examination, during which time X-ray pulses are emitted to the subject periodically to obtain X-ray images of the subject from many directions. The obtained X-ray images are observed continuously. Means for obtaining the X-ray images includes means for taking optical images produced by the image intensifier by use of a movie camera and means for taking the images by use of a television camera.
With the prior art, the continuous observation of many X-ray images which vary continuously in the direction of line of view causes an observer to imagine as if he or she rotated around the subject under examination continuously thus permitting stereoscopic vision of images of the subject. It is therefore required to always change the direction of line of view of the X-ray images. With the continuous observation of only one X-ray image, stereoscopic vision is impossible. The static image presentation for careful observation of the subject for diagnosis will provide no sensation of stereoscopy. Because the stereoscopic vision depends to a large extent on the human sensibilities, the degree of the sensation of stereoscopy acquired will differ from person to person. For this reason, some people may recognize an actual distance relationship between two objects erroneously. Furthermore, the sensation of stereoscopy is related to display speed for continuous observation, thus involving much difficulty in achieving the optimum sensation of stereoscopy.